Headlight stopped working

[bonio]

Was working just fine. Then suddenly not. Now when I turn the key, just the little parking light comes on (yes, it has one; it's main function is to drain the battery when you leave it on "P"). But when I press the flasher switch (you can see why this is a great bike) both beams come on full power. So there's nothing wrong with the lamp or the wiring to it. There's no way to switch the dipped light off - the only light switch goes between dipped and main. 

Any ideas on how to hunt the problem down?

 

PS For anyone who's just read my tail-light-rescue post, I found out this problem before fixing the tail lamp, so it's not caused by something I've cocked up in the repair.

[Mississippi Bullfrog]

There's often a different fuse for the headlight as opposed to the flasher switch. So maybe take a look at the fuses?

[Simon Davey]

Can't help thinking it might be the lighting relay? 

 

[bonio]

Since posting, I've been reading up on thumpertalk. It seems a common problem is dirt or corrosion gets into the starter switch, and this affects the operation of the relay that kills the headlamp when you start the bike. A number of people said they had the problem, so that's where I'm going to start. After that it's check the relay, then the wiring. The only has one fuse, so that's kind of checked already.

[bonio]

I took the starter switch assembly apart, gave the inside a couple of shots of WD40 and happy days it's working.

Time get the MOT rebooked.

 

[Simon Davey]

Awesome 

[Mississippi Bullfrog]

7 hours ago, bonio said:

I took the starter switch assembly apart, gave the inside a couple of shots of WD40 and happy days it's working.

Time get the MOT rebooked.

 

I suggest going back and putting something in there that will keep it lubricated.  WD40 can free things off but it's not a lubricant.  

[Stu]

If they are dual filament bulb then your low beam might have popped? 

[Fiddlesticks]

On 23/03/2024 at 08:16, bonio said:

I took the starter switch assembly apart, gave the inside a couple of shots of WD40 and happy days it's working.

Time get the MOT rebooked.

 

We have just developed exactly the same fault . Of course, it's while we're on a bit of a tour. Have bought WD40, will check fuses etc. tomorrow.

[bonio]

Best o' luck @Fiddlesticks

Edited March 29, 2024 by bonio

[Fiddlesticks]

We still have the led spots and centre small bulb, at least.  Reading the Triumph forum it's likely to be a bad connector under the tank.

 

If not possible to fix on the road, I'm wondering about the feasibility of blocking out the top half of the headlight grille with black tape - so as not to blind oncoming traffic - and using the main beam.

[bonio]

On 23/03/2024 at 09:46, Angela Collen said:

Really glad you've worked it out, hope mot goes well

Haha, it almost did. I passed with an advisory marked "urgent repair" because the number plate is illuminated by a red light, not a white one.

When I got it home I took a look and saw what I'd done - I'd put the tail light on upside down, so the white light is shining upwards onto on the luggage rack instead downwards onto the the number plate. At least it's an easy fix.